On Tuesday the Fourth Week of Lent our Church invites us to first read and reflect on a passage from the book of Leviticus (19:1-18, 31-37) entitled "Right conduct towards one's neighbor". Our treasure, which follows, is from a sermon by Saint Leo the Great, pope.
Saint Leo became pope in the year 440. Saint Leo was a Roman aristocrat, and was the first pope to have been called "the Great". Saint Leo is known as one of the best administrative popes of the ancient Church. His work branched into many areas of the church, indicative of his notion of the pope's total responsibility for the flock of Christ. In the 96 sermons which have come down to us, we find Leo stressing the virtues of almsgiving, fasting, and prayer, and expounding Catholic doctrine with clarity and conciseness, particularly the dogma of the Incarnation. Leo is perhaps best known for having met Attila the Hun in 452 and having persuaded him to turn back from his invasion of Italy.
Saint Leo the Great's primary contribution to the teachings of the Catholic Church was his clear articulation of the two natures of Christ—fully divine and fully human—united in one person. In his famous Tome of Leo, he explained that Jesus Christ possesses both natures without confusion or division, a teaching that was affirmed by the bishops at the Council of Chalcedon and became a cornerstone of Catholic Christology. Leo also strengthened the understanding of the authority of the Bishop of Rome as successor of Saint Peter the Apostle, helping shape the doctrine of the papacy while safeguarding the Church's teaching about who Christ truly is.
The name "Leviticus" was given to the third book of the Pentateuch by the ancient Greek translators because a good part of this book deals with concerns of the priests, who are of the tribe of Levi.
The primary message of the Book of Leviticus is that God is holy, and His people are called to live in holiness in every aspect of life. Through laws about worship, sacrifice, moral conduct, and daily living, God teaches Israel how to remain in right relationship with Him and with one another. At its heart is the call: "Be holy, for I the Lord your God am holy" (Lev 19:2), showing that holiness involves not only proper worship but also justice, mercy, and love for neighbor. The book reveals that approaching God requires reverence, repentance, and purification, while also pointing forward to the deeper fulfillment of sacrifice and holiness in Jesus Christ.
